Hi sir i have acer aspire 4520 laptop for past few days when i turn on my laptop the power wil on but displa will black (it will not be going to on , just dead screan ) but remaining all the process is ok . but in some time some times it will work and after few hours the display will become freeze so wht the problem behind this can any one help regarding this matter thanking you.

Is Ur keyboard indicator lights are coming up when u switch on the lap ?

Common problem with acer laptops. send it to acer to get if fixed. some people bake their motherboards and it sometimes works - but i dont reccomend it. Youtube Motherboard Baking.

You may have a back light problem, can be caused by a faulty inverter or a faulty CCFL lamp. Please click on this link and follow my instructions to determine the fault and fix :-
http://www.fixya.com/support/r3598095-faulty_laptop_lcd_screen

i mean this is a videocard problem...you have to change the videocard ..
if the schreen is visible but with low light this can be a lcd inverter problem. but if the lcd some time goes and later freeze this is video card faulty... if you have knowledge...its possible to look if the videocard are not inserted diectly in the mainboard...so you can change only the videocard....
disassemble the video card and search on ebay the same model... and change the card...if the card is integrated in the mainboard...i am sorry you have to change the mainboard. control if you can able to estrct only videocard. control in the model support if your pc have integrated videocard or not??!?!? sorry for my bad english i hope to have help you.

Hello mcrey, hi, your acer aspire has system board issues, this board needs replacement, the only advice worth giving is have this laptop serviced by a technician, for board replacement.

hi, yes the laptop will shutdown if you press power button.
it send command to OS that it required to shutdown in emergency so it shutdown in force. so do not shutdown by pressing the power button. use start> shutdown option.
i hope this will resolve the issue.

IT COULD NVIDIA DISPLAY IC PROBLEM,GET IT REPLACED.
DHARMAKKAN

Can you hear the system fan running? If the fan fails, the PC shuts down itself to protect the processor from FRYING.

download drivers from http://www.laptops-drivers.com/acer-notebooks/free-download-driver-acer-aspire-4520.html

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